|
Tone Remote
Tone Remotes are employed
to remotely control transmitters. A remote may be located in the
same building as the transmitter, or they may be separated by
many miles and use telephone lines or microwave links to connect
the transmitter with the tone remote.
Control signals and voice
are sent from the tone remote, over the dedicated pathway, to
the transmitter. It is necessary to install an interface board
in the transmitter to convert the tone remote signals to actual
channel and Push-to-Talk (PTT) functions.
|
|
| Standard Tone Remote Frequencies |
Relative Levels |
Tone Duration |
High Level 2175 Guard Tone |
10 dbm |
120 msec |
1950 Hz Transmit F1 Function |
0 dbm |
40 msec |
1850 Hz Transmit F2 Function |
0 dbm |
40 msec |
2050 CTCSS Monitor Function |
0 dbm |
40 msec |
Low Level Guard Tone |
-20 dbm |
20 msec |
Voice Peaks |
0 - 5 dbm |
|
Other tones may be employed to provide additional functions.
These other tones will use the same 0 dbm level and 40 msec timing
as those shown above.
Tone Freq. |
Function |
Function |
Function |
1750 |
Receiver 2 |
Mute |
|
1650 |
Receiver 2 |
Mute |
|
1550 |
Max Squelch |
Repeater Off |
CTCSS On |
1450 |
Min Squelch |
Repeater On |
CTCSS Off |
1350 |
Freq. 3 |
CTCSS 1 Select |
Option 1 On |
1250 |
Freq. 4 |
CTCSS 2 Select |
Option 1 Off |
1150 |
|
CTCSS 3 Select |
Option 2 On |
1050 |
|
CTCSS 4 Select |
Option 2 Off |
There are two ways the Tone Remote signals are sent.
Single Tone Format
Function Tones are sent as a separate item from the PTT signal.
A Function Tone is sent at 0 dbm for 350 msec. While a PTT signal
(2175) is sent at -10 dbm for the entire time the voice is being
transmitted.
Sequential Tone Format
In this method, a guard tone of 2175 is sent at +10 dbm for 40
msec, followed by a function tone at 0dbm for 40 msec, which is
then followed by a continuous PTT tone of 2175 at -20 for the
entire duration of the voice transmission.
|
| 
